Clinical Research Directory

Inclusion Criteria: * (1) Age 50-70 years with overweight or obesity (BMI ≥ 24 kg/m²); * (2) At least one of the following three: metabolism-related fatty liver disease (diagnosed by ultrasound); pre-diabetes; type 2 diabetes mellitus with HbA1c \<7% without glucose-lowering drug therapy; * (3) Agreed to participate in the trial and could adhere to the follow-up and visit the hospital on their own; signed the informed consent form. Exclusion Criteria: * (1) Patients with tumours; * (2) Patients with autoimmune diseases (excluding Hashimoto's thyroiditis); * (3) Severe cardiovascular disease or cardiac insufficiency; * (4) Systolic blood pressure \> 160 mmHg or diastolic blood pressure \> 100 mmHg; * (5) Chronic obstructive pulmonary disease; * (6) Chronic active hepatitis or cirrhosis; * (7) Chronic renal insufficiency; * (8) Stroke patients; * (9) Severe haematological diseases; * (10) Infectious diseases; * (11) Mental illness; * (12) Other conditions that, in the opinion of the investigator, may affect the results of the study; * (13) Those who have used NMN or other anti-aging agents within six months; * (14) Premenopausal women; * (15) ALT, AST values are more than three times higher than the upper limit of the normal reference range;